川东北元坝气田高温抗硫环空保护液研制及应用

Study and Application on High Temperature Sulfur Resistance Protection Fluid of Yuanba Gas Field in Northeast Sichuan

针对元坝气田高温含硫化氢气井,为降低油套管腐蚀程度,确保气井长期安全生产,文章通过优选密度调节剂、缓蚀剂、除氧剂等添加剂种类及加量,形成了一套以复合甲酸盐溶液为基液的环空保护液体系。该产品密度1.0～1.6 g/cm^3可调,具有良好的高温稳定性能,在160℃条件下钢片腐蚀速率仅为0.0644 mm/a;抗H2S、CO2腐蚀性能优异,相应条件下钢片腐蚀速率仅为0.0005 mm/a。在元坝气田应用15口井,共计配液量约3000m^3。

Based on the high temperature hydrogen sulfide gas well casing, in order to reduce the degree of corrosion tubing and casing, and ensure long-term safe production, through the optimization of the density moderating agent, corrosion inhibitor, oxygen and the amount of species, the paper developed a kind of suitable for the well annulus protection fluid. Performance evaluation results show that, the annulus protection fluid density up to 1.3 g/cm^3; it has good high temperature stability performance; high temperature corrosion rate is only 0.0644 mm/a; under the condition of high temperature resistant to H_2S, CO_2 excellent corrosion resistance, corrosion rate is only 0.0005 mm/a; and the annulus protection fluid wide raw material sources, low price, and can be widely applied in high temperature sour gas wells. Application of 15 wells in Yuanba gas field, the total amount of liquid is about 3000 m^3.